The present invention relates to an vehicle brake rotor and more specifically to a modular brake rotor having friction rings secured to the ribs of a core.
Wheeled vehicles are typically slowed and stopped with a braking system that generates frictional forces. One known braking system is the disc braking system which includes a rotor attached to one or more of the vehicle wheels for rotation therewith. The rotor has an annular peripheral section comprised of a pair of annular friction rings joined together by spacers or ribs in a mutually parallel, spaced apart relationship to form spaces or vents therebetween. Friction surfaces are disposed on the opposite, outwardly facing annular surfaces of the friction rings.
The disc brake system also includes a caliper assembly secured to a non-rotating component of the vehicle, such as the vehicle frame. The caliper assembly includes a pair of brake pads, each having a backing plate and brake lining material attached thereto. A pad is disposed adjacent each friction ring such that the brake lining material is adjacent the friction surface. The caliper assembly includes at least one moveable piston operatively connected to the backing plate of at least one of the brake pads. When the driver brakes the vehicle, hydraulic or pneumatic forces move the piston which clamps the brake lining material of the pads against the friction surfaces of the rotating rotor. As the pads press against the moving rotor friction surfaces, frictional forces are created which oppose the rotation of the wheels and slow the vehicle.
It is known to assemble rotors from separate components to form a modular rotor. Buyze (U.S. Pat. No. 3,486,218) discloses a ventilated modular rotor having a core including a mounting flange and a corrugated spacer stamped from a single piece of sheet or coil steel stock. Annular friction rings, formed from sheet or coil steel stock, are secured to the corrugated spacer by welding, brazing or adhesives. However, the corrugated ribs have only a small amount of surface area in contact with the friction rings which reduces options available for securing the friction rings to the ribs. It is desirable to produce a modular rotor having a core with ribs that have mounting surfaces of sufficient surface area for securing friction rings thereto in a variety of manners.
It is also desirable to produce a modular rotor with a cast core having ribs secured to the friction rings for providing a strong, durable rotor that is cost efficient to produce. Metzler, et al (U.S. Pat. No. 5,107,966) teaches joining a cast hub to a cast friction portion using compound casting. A hub portion including a plurality of radially extending projections is cast from a material having a high tensile strength. A friction portion including spaced apart friction rings joined together by a plurality of webs running in the axial direction is then cast around the hub portion. The friction rings clasp the radially extending projections to secure the friction rings to the hub portion. However, compound casting will not enable adhesives to be disposed between the friction portion and the hub portion since the casting of the friction rings will incinerate the adhesive. It is desirable to reduce the transmission of vibrations between the friction rings and the hub portion by using a construction technique which would allow the use of adhesives therebetween.